Physiology of Sleep

REM Sleep• 5-30 minutes with 90 minute-intervals• Active dreaming (dreams are remembered)• Active body movements• More difficult to wake up with sensorystimulations• Waking up in the morning generally coincides with thelast REM period.• Decrease in muscle tone (except respiratory and eyemuscles)• Irregularity in heart and respiration rate.• 20% increase in brain metabolism